Series-connected envelopes



April 1957 I c. J. REUTER I 2,790,593

SERIES-CONNECTED ENVELOPES Filed April 29, 1953- INVENTOR. CLARENCE J. REUTER United States Patent 2,790,593 SERIES-CONNECTED ENVELOPES Clarence J. Renter, Springfield, lll., ass'ig'nor, by mesne assignments, to Ua'rco Incorporated, a corporation of Illinois Application April 29, 1953, Serial No. 351,813 7 Claims. Cl. 229-69) This invention relates to series-connected envelopes and is particularly concerned with a method of making envelopes-having longitudinally extending flaps in seriesconnected form.

The advantages of series-connected envelopes in connection with continuous strip feeding means is well known. Heretofore, envelopes having sealing flaps extending across the short dimension of the envelope, have been made in series-connected form. However, so far as I am aware, conventional mailing envelopes, having the sealing flap extend along the longer dimension of the envelopes have never been made in this manner because it has been considered necessary to feed such envelopes in the longitudinal direction and the capacity of the envelope making machine would be reduced by increasing the feeding time for each envelope.

Heretofore envelopes having a sealing flap extending along one of the long edges have been fabricated in conventional manner and then joined to a continuous feed strip in a separate operation, as evidenced by the Sherman Patent No. 2,013,844;

The present invention involves the fabrication of a series of envelopes having sealing flaps along the long edge in a continuous strip, with the flaps extending transversely to the line of feed so that the capacity of the envelope fabricating apparatus is not reduced by excessive feeding time for individual envelopes.

It isan object of this invention to fabricate envelopes in continuous strip form by adhering die-cut front portions having a sealing flap to a continuous backing strip of paper as the backing strip is being fed through the envelope machine.

It is another object to simplify the method of fabrication of series-connected envelopes so as to make them economical to manufacture and convenient to feed through typing or printing apparatus.

With the foregoing and other objects in view which will appear as the description proceeds, the invention consists of certain novel features of construction, arrangement and combination of parts hereinafter fully described, illustrated in the accompanying drawing, and particularly pointed out in the appended claims, and in the novel method of fabrication, it being understood that various changes in the form, proportion, size and minor details of the structure or variations in the step-by-step sequence of the described method may be made without departing from the spirit or sacrificing any of the advantages of the invention.

For the purpose'of facilitating an understanding of my invention, I have illustrated in the accompanying drawing a preferred embodiment thereof from an inspection of which, when considered in connection with the following description, my invention, its method of construction, manner of assembly and operation, and many of its advantages should be readily understood and appreciated.

Referring to the drawing in which the same characters of reference are employed to indicate corresponding or similar parts throughout the several figures of the drawmg:

Fig. 1 is a perspective view of a continuous series of backing" strips being fed from a roll and illustrating the steps of the method for fabricating a strip assembly of 2,790,593 Patented Apr. 30, 1957 series-connected envelopes having sealing flaps extending transversely of the line of feed;

Fig. 2 is a longitudinal sectional view through a series of envelopes, taken along the line 2-2 of Fig. 1;

Fig. 3 is an elevational view of the die-cut front half of the envelope provided with heat sensitive adhesive by which it is secured to the backing strip; and

Fig. 4 is a perspective view of an individual envelope after the continuous feed strips have been removed from the opposite edges.

Referring to the accompanying drawing in detail, the Fig. l illustration constitutes a symmetric view representative of the various steps of the novel method performed during the fabrication of a strip of series-connected envelopes from a roll of stock forming the backs of the envelopes and a series of die-cut pieces forming the fronts and sealing flaps. As illustrated, a roll of paper stock 11, which constitutes the backing strip of the envelopes, is fed along a predetermined path past a plurality of work stations in intermittent steps. Several operations, hereinafter described, are performed on the backing strip 11 at the various work stations during the feeding of said strip through the envelope machine, and the pause between each feeding step is long enough to perform any one of these operations. The backing strip 11 is wider than the die-cut front portions 12, and is weakened along parallel lines 13 which extend longitudinally of the backing strip and are spaced apart a distance equal to the width of the die-cut portions 12. The strip 11 is also weakened along transverse parallel lines 14 which are spaced apart a distance equal to the height of the body portion of the die-cut front portions 12. The lines 14 terminate at their intersection with the weakened lines 13. The marginal portions 15 are each provided with a continuous series of uniformly spaced perforations 16 adapted to engage feeding pins provided on a typing or printing machine (not shown) through which the envelopes are fed when they are to be addressed. The backing strip may be weakened and perforated simultane ously, or in successive steps, as desired. The backing may be weakened either by scoring the strip deeply along the indicated lines, or by slitting or perforating the strip along intermittent lines with the unslit portions very short so that the ultimate separation of the envelopes along the indicated lines may be accomplished without difiiculty.

v The die-cut front portion has a conventional sealing flap 17 extending from one of its long edges, and water soluble glue 18 is applied to one edge portion of the flap for sealing the envelope. Heat sensitive adhesive is ap plied to three edges of front 12., as indicated at 19, being admitted only from the edge adjacent flap 17. The die out front portions 12, with their flaps extending in the same direction, are stacked above and on one side of the path of the backing strip in the envelope machine with the adhesive 19 on the underside of each front. As previously stated, the backing strip 11 is fed through the machine in intermittent steps and the front portions 12 are applied individually to the backing strip 11 during the pauses between successive feeding steps. It is preferred'to apply the fronts 12 by blowing them from a position just above the side of the backing strip at a rate synchronized with the travel of the backing strip so that a front is positioned on the backing strip between each pair of adjacent weakened lines 14 with a flap 17 overlapping the adjacent front 12. Heat is applied at two spots 29 and 21 after the front 12 has been properly positioned to hold it temporarily against movement relative to the backing strip.

As the strip 11 and fronts 12 move forwardly through the envelope machine, the flaps 17 assume an angular position, as shown in Fig. 2. The upturned flap 17 of each envelope engages the side of a heating shoe 22 and is turned upwardly at right angles as the strip moves to position the precedingenvelope under the shoe. The shoe 22 is U-shaped and fits directly above the heat sensitive adhesive 19. The heated shoe 22 is pressed down against the three edges of the envelope front 12 to which heat sensitive adhesive 19 has been applied, to adhere the envelope front to the backing strip 11. As the strip of series-connected envelopes is moved forwardly, the shoe 22, which is raised only a short distance to permit movement of the strip, presses the flap 17 of the Succeeding envelope rearwardly into engagement with its own envelope. The water soluble glue which has been applied to the fiap 17 terminates short' of the area of. the flap which is contacted by the shoe, as shown at 23, Fig. 4, so that the flap 17 is not inadvertently sealed to its envelope by heat from the shoe.

The method of forming the envelope fronts separately and applying them to the backing with the flaps overlapping the preceding envelope permits the envelopes to be arranged transversely of the backing strip and thereby reduces the amount of longitudinal travel of the backing strip per envelope and proportionately increasing the capacity of the machine.

The envelopes are preferably used in series-connected form, but may, if desired, be removed from the strip at any time and used separately. The envelopes are ultimately separated merely by removing the marginal strips 15 along the weakened lines 13, and then separating each envelope from the adjacent envelope along the weakened line 14.

It is believed that my invention, the method of construction and assembly, and many of the advantages of such method should be readily understood from the foregoing without further description, and it should also be manifest that while a preferred embodiment of a strip of series-connected envelopes has been shown and described for illustrative purposes, the structural details are, nevertheless, capable of variation within the purview of my invention as defined in the appended claims.

What I claim and desire to secure by Letters Patent of the United States is:

1. A method of making a strip of series-connected de tachable envelopes including the steps of feeding a backing strip along a predetermined path in intermittent steps, weakening said backing along parallel longitudinal lines spaced inwardly from opposite edges of said strip and along lines extending transversely between said longitudinal lines, perforating both longitudinal marginal portions of said strip, positioning an envelope front, each previously treated with heat sensitive adhesive at predetermined areas, on said backing strip between each adjacent pair of transverse weakened lines, each of said envelope fronts having its edges coinciding with said longitudinal weakened lines, adhering two opposite edges of each of said envelope fronts to said backing strip at limited areas to hold them together temporarily, then applying heat over the entire area previously treated with heat sensitive adhesive to adhere each of said envelope fronts to said backing strip along two edges adjacent the longitudinal lines of weakening and one edge adjacent a transverse line of weakening to form a strip of top flap envelopes.

2. A method of making a strip of series-connected detachable envelopes which comprises the steps of feeding a backing strip past a plurality of work stations along a predetermined path in intermittent steps, weakening said backing strip along four lines defining a rectangle having a surface area equal to the surface area of the completed envelope, applying heat sensitive adhesive to each of a plurality of envelope fronts. positioning one of said envelope fronts in each of said rectangular areas, with the heat sensitive adhesive in contact with the surface of said backing strip, applying heat to a limited area adjacent opposite edges of said envelope front to secure it in place temporarily, and then applying heat over the entire area to which heat sensitive adhesive has been applied to adhere each of said envelope fronts to said backing strip.

3. The method of forming air assembly of top-flap, series-connected, detachable envelopes, comprising the steps of: advancingan envelope backing strip along a predetermined path; positioning each of a plurality of envelope portions transversely of the backing strip in timed relation to the advance of the backing strip so as to space said envelope portions longitudinally of the backing strip; adhering each of said envelope portions along three sides to a transverse portion of the backing strip to form fronts and backs of envelope pockets having transverse openings, the fronts of each of said pockets carrying a closure flap; and weakening said backing strip along a series of transverse lines each positioned between an adjacent pair of envelope pockets to facilitate the detachment of individual envelopes from the assembly.

4. The method of forming an assembly of top-flap, series-connected, detachable envelopes, comprising the steps of: advancing an envelope backing strip along a predetermined path; coating heat-seal adhesive in a U- shaped pattern upon three marginal edges of one side of each of a plurality of rectangular envelope fronts each carrying a closure flap on its fourth marginal edge; positioning each of said rectangular fronts transversely of the backing strip in longitudinally spaced relation so that each closure flap extends transversely of the backing strip; applying heat successively to said U-shaped patterns of heat-seal adhesive on each envelope front to heat-seal said three marginal edges of each envelope front to the backing strip to form a series of envelope pockets having transversely extending pocket openings; and weakening said backing strip along transverse lines, each positioned between an adjacent pair of envelope pockets to facilitate the detachment of individual envelopes from the assembly.

5. An assembly of top-flap, series-connected, detachable envelopes, comprising: a continuous backing strip of envelope material having longitudinally spaced, transversely extending lines of weakening to provide a series of rectangular backing strip portions, and a plurality of rectangular envelope portions each having three marginal edges heat-sealed to a backing strip portion between an adjacent pair of said lines of weakening to cooperatively provide the fronts and backs of a series of envelope pockets having transversely extending openings, each front of an envelope pocket having a closure flap secured thereto.

6. An assembly as specified in claim 5 in which each of the envelope portions is die-cut to form a rectangular envelope front having a closure flap hinged to its unsecured marginal edge.

7. An assembly as specified in claim 5, in which the envelope portions are formed individually, each of said envelope portions being die-cut to form a rectangular envelope front having a closure flap hinged to its unsecured marginal edge, each of said envelope fronts being substantially the same shape and size as each of the backing strip portions.

References Cited in the tile of this patent UNITED STATES PATENTS 

